Block insert



FIG. 1 is a rear, top side perspective view of a block insert of the new design;

FIG. 2 is a rear side elevation view thereof;

FIG. 3 is a front side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines depict the bounds of the claimed design. The broken lines form no part of the claimed design. 

CLAIM The ornamental design for a block insert, as shown and described. 